Novichok that killed woman came from bottle, police believe

In a statement on Friday, the Met Police said they had discovered a bottle containing Novichok in Rowley's home.

It was taken to the Defence, Science and Technology Laboratory at Porton Down, Wiltshire, for tests.

Rowley, 45, and his partner Dawn Sturgess, 44, collapsed at his house within hours of each other on June 30. Rowley remains in hospital where he has regained consciousness.

More than 100 police officers had been searching for the source of Rowley and Sturgess' exposure in the towns of Amesbury, where they lived, and Salisbury, where the Skripals were poisoned.

Further scientific tests will determine whether the toxic nerve agent came from the same batch that contaminated former Russian spy Sergei and his daughter, Yulia Skripal in March.

Moscow has strongly denied any involvement in the poisoning.

"Inquiries are under way to establish where the bottle came from and how it came to be in Charlie's house", the spokesperson added. "However, we can not guarantee that there isn't any more of the substance left and cordons will remain in place for some considerable time", Metropolitan Police Assistant Commissioner Neil Basu said in a statement.

Staff from the Organisation for the Prohibition of Chemical Weapons (OPCW) will travel to the United Kingdom to independently confirm the identity of the nerve agent which led to Ms Sturgess's death.

"During their visit they will be able to collect samples to inform this work".

The samples will be analysed at "highly reputable global laboratories designated by the OPCW", a spokesman said.

"The way that we do this might start to look slightly different from next week, when private security guards will join my officers on some of the cordons".

A post-mortem is due to take place next week to establish Sturgess' cause of death and an inquest will be opened and adjourned on Thursday, July 19.

"Given the ongoing incident in Salisbury and Amesbury, we are taking highly precautionary measures to ensure public safety", police said, referring to the poisoning of two more people in Amesbury last month.

Public Health England has reiterated its advice to members of the public and urged residents not to touch or pick up foreign objects.